Re: Control System for Hydro Generator

03/14/2017 10:20 AM

Usually it is a penstock (that includes necessary flow regulation valve(s)). Or if you want your generator to run 100% flow for the amount of head present at the penstock, you only need a nozzle to the turbine that produces this amount of flow all the time.

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Re: Control System for Hydro Generator

03/14/2017 10:35 AM

Before you control the generator you need to know what you're controlling. What type of generator, AC/DC, Synchronous/Induction, standalone/paralleled (I hope not), etc., etc. But first you need to do a site survey to determine the amount of potential and kinetic energy that you can capture; things like dimensions, flowrate, seasonality, head, etc. Then you need to determine what type of waterwheel will operate under the flow/speed constraints determined by your site survey.

If you're starting to think that this is more involved than you first thought, you should Google on mini-hydro generators to start filling in the blanks.

Re: Control System for Hydro Generator

03/14/2017 11:48 AM

There's not so much materials in google for Archimedes Screw Generators control system. I am interested to find out. My thinking is that it's simple, but I bet there are establish schematics diagrams on this.

Re: Control System for Hydro Generator

Re: Control System for Hydro Generator

03/15/2017 8:39 PM

The controls & theory are the same for all generating sets. The mechanical items you adjust are different for different prime movers, you control water flow into the screw, valve or weir, even vary the inclination of some, that adjusts the speed/frequency. This type is interesting in that you typically start the turbine moving with an outside force, before it starts generating, maybe because of the large reduction gear. Those controls & changing between motoring & generating and controlling water flow during the change will be special controls compared to other types of machines, and maybe not that common. Otherwise all of the instruments & schematics will be applicable.

The controls for voltage are the same, they stay with the generator, don't care what the prime mover is.

Re: Control System for Hydro Generator

Presumably you want to produce AC at a constant frequency and voltage.

The generator will have a voltage regulator, adjusting the field current to give correct volts, in the usual way.

You know what speed gives right frequency, so I think you measure actual speed, compare it with required, and adjust water input via a throttling valve till equal. Accommodates varying power demand. Problem with that is at reduced demand, energy is wasted by throttling (pressure drop) across the valve. Ideally it would be better to vary the flow but give full available pressure at the turbine (eg by varying penstock area) but I can't think of an easy way to do that, perhaps somebody can. It may not be a problem in your case, depending on the details.

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